resquested_toopings = ['mushrooms','green pappers', 'extra cheese']
for resquested_tooping in resquested_toopings:
        if resquested_tooping == "green pappers":
            print("Sorry, We are out of green peppers right now")
        else:
            print("Adding " + resquested_tooping + ".")
print("\nFinished making your pizza!")

resquested_toopings = []
# resquested_toopings = ['mushrooms','green pappers', 'extra cheese']
if resquested_toopings:
    for resquested_tooping in resquested_toopings:
        print("Adding " + resquested_tooping + ".")
    print("\nFinished making your pizza!")
else:
    print("Are you sure you want a plain pizza?\n")

#5.4.3 使用多个列表
available_toppings = ['mushrooms','green pappers', 'extra cheese', 'olive', 'pineapple',]
resquested_toopings = ['mushrooms','french fries', 'extra cheese']
for resquested_tooping in resquested_toopings:
    if resquested_tooping in available_toppings:
        print("Adding " + resquested_tooping + ".")
    else:
        print("Sorry, we don't have " + resquested_tooping + ".")
        